SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c47572839023347bcdd65fda186b79d14ba26b1dfeaaff965e1e06659ced92dd' 
  AND token = 'wgLpNETPDrfmpIoeLGioRgBqYVtkoVRa/sI95ShsnCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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