SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce187137a54afa525021f1100dbe1cf7e3193d89747a40c87cbbd062168b220d' 
  AND token = 'L8PkgDQLWhLRnurbx2S2khxv5DTF/fnVV9VEdev4uto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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