SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73105ae1163f3f513e6fe26f07d9776315de3ea4a348f554868a6c676819d9a1' 
  AND token = 'wNDh4+/1e/BszzkZUzFm0cgU4FNHbY4KaIzbmivGkHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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