SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '961fdc8059a25de4919ffcd96b5819e30e40702981ab5129751ab0bcf606aad4' 
  AND token = 'AarJtvUAAGbYkgm6+ATwBQ5pDGBEXaAQPpJjn8cxO2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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