SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1e4d90443b6e9ce29b6fa08d4872d01184362b7e91747080cacfb12878ccfc6' 
  AND token = 'XGWSOYM1646oLPk2QGDJoYROxssErt78ACiwmC9a1xQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}