SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5daab39f56a5fbcd13beef2a207bc8615f9502e4944ce39f66f3a191d519ed15' 
  AND token = 'jD4g7yIIO99csluFpILsT9q0KWIKnu/7Hy9F1AQRagk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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