SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33f327b878416e59521fbece8bf9153fedb832d3a77169d0b363b6ccaa4ccd65' 
  AND token = 'jBsX4vER6q+y5nGASe6XjmFOnLzUZRq6hg6/iZEkaTg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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