SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fced3904fca125101a21203fd68772bd884ca94cdfa0858312892958d65e9d4a' 
  AND token = 'gy71dA4uNlqaFU0nHnNwBrr3E55U/csCWVqjgutzMgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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