SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8b10f10d2f56eb74f1f77aac434d0549090f89ebac8fec31b27e853cb3116dce' 
  AND token = 'gI+XIVRSJPncqx9L1ogEcgANQdil/VWGFccu8X8jKNw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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