SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ab2f4a5dec1f7af19e0f0f9671d84c7067a81a26ee92d7d8555c0216931e1ea' 
  AND token = '3Fh5f/fO2E4uECqzK3xowIm/VylLFJHC4fvGnlpZi7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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