SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10384fa0a2c682d9da0dd5f2f56e05173de949361adc7b2a32785e60a914faa6' 
  AND token = 'mL48a8a4uGh43MZrb1VuUnyVJLVn3zrWRvvVQga6q2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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