SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '498c804ff77ef1502a5eb351ebd045c9e36437ee751f6b5053da90a545919284' 
  AND token = 'JBhQ23l4sId3S69JEs6U3lNAQLnMoUeUhFa79X3Xx/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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