SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a145994904d4f49da87953e104671a30e9cc73fde4fc20bc91979141c5acd33' 
  AND token = '43pXqqhRB4ET4+RrsJGyasjTvcyxguhnGfdrCK9sEJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}