SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5989437f0a10f9d17b7a571fb995fde9d386a832e33632d6668788ec8a010ff0' 
  AND token = 'dregoHWih1v2ur3oyg3zcoV0vP6L5PzOvI4w5HQ3xG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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