SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57b2541cc9f7193f37c31491023da2fe294fbcc5f5323f5322686d57ab371a78' 
  AND token = 'ZNlcoLRU+PKqDy0auh/Pk1ng0xY4VveKsoMI5H+wHx0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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