SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a6f8084aafc2c166a153fb180883283d54f5f30ce7990e72bb06a968a0b7b77e' 
  AND token = 'nYY/6vhqEK+hVEBR8Wl7KO436v7pFhTLeRGgTcJ4Qrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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