SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a6f7b20abcfcb862458255fde7b083b7032b181f400263c0f82b8557216df5c' 
  AND token = 'ZYdGCXzT8aZRaoHTZodctvXzr4eAQS8vnVT3pJ1hzNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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