SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d77756746db165279651d3ad7a72553a5567b533c0db33f564ea0fe29151304' 
  AND token = 'dhbpUb2DGGAnMSzUYPOe8VpF+rQgTkl7L/v8bYlGpB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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