SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '74b35368f80da3e409a134d1387da2f8fcf6c589be74bf011e96cbcd343fff48' 
  AND token = 't0AFZ0mp9FepqaTYWH7VTV3yhwt1KG0w4q/qRyWTEs0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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