SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1dffab51141df36ce2777a6ffb2c227194424c389006d5825861b3bf68ab28b9' 
  AND token = 'aClC/zWOWgGFozi2zqByTnRVneu1wXTTqaJNiD00nqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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