SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dba0257f5c3620c31297b8a751f5a2b3245f631fcaa2a0a8a2f1007cea9d71a2' 
  AND token = '1Tv1IOM1qqaNanAUlgOvYjCE2c+No0bKPm6q9DP+0vY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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