SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2d086c3df110d7d94b4b4ca9a80d6867c723ab04c722405773b283646706569' 
  AND token = '/YIzYL99GVfb5REqBIfPAcoVQ2YRbNXb6jZquIwKt/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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