SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c79aa6936d0dcf50751395a0ef3e91454c04fed6ce03a0144e8dd9eeb0463004' 
  AND token = 't3nvz5vtLdpGyq/CB8OKWVVFs5YKtmc91tA70FcemFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}