SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1756a144e8516e7b82ce6b01c7f67abdb268d9454197907317fd6184e335acb2' 
  AND token = 'lHc1vCT7ZvlgK/2GUWhxVrznEYUyjzZW6uTwOsLUovA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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