SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be40b44486f8455d8b19061b32acc1211ed985030fd3aef15db270b79b3129e4' 
  AND token = 'lw4fKVgYDXiAvMt5VTEXKUXPQ07zTnuwhH6zHgwcxw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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