SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22826c08b1e67556ef32b988cd72ad198e431ec9a72cee9766f7bf19f74374f3' 
  AND token = 'IhVeLl1yg5aSDbfJ8c7Dw6jUzVoaFI+38RDRW1miY1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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