SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5a23040c0b37afe297d0dfaae32f1cbc5be188a9719d982b7d8bc441c187e15f' 
  AND token = 'SQEPLdpBXJKzKbh+UaRu0Gc7m4q+QeJYau+OP8FpAHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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