SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f2fb0458baa8643987f1a7d873e42d7a9b690a5fc7cd4454c7d03bf9cc5a18f' 
  AND token = 'vWjqhw8VfKBE1a2GItWMdhKQUGQz0BAJOwEvc5ML6U4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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