SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '744a2eb9c9aa3bcde0f335a732444fff86335cd530a35d940709698dc84ad653' 
  AND token = 'yUDoQQvQK5nzJ92zI6123ceRq07OIgvCqm/wJLZoVpo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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