SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dd54bc3b0fd03543bc6f3feb9562627f06b8a1bfa607049f688a3708f84dd5d0' 
  AND token = 'A70VzXd1cbam5ISuA3/WG9pNooiJFjWmMGTEN/0q7Ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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