SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '36d6f7a4bfb58f172f389ee4d5e15fab7bdd2b27591459b7356c32aaeb968392' 
  AND token = 'js1ultoQZfD6PVj0XcLoMIG2OVVHvl26P4JVBoZl75s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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