SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa6516e354045b19a1700cf185ca15fcf83814b4ae7e24c65cb836ab4cb12945' 
  AND token = 'oLkFDVabHdllPCbpemKtHexr1ziU9+ZhTy23PcIbaaY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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