SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e0818c95ceea0bd561717b7eb69e8d453d24a40bfb479b9f39bae45472df266' 
  AND token = 'njLarGsl8MC3bRONZ5enYnLNe5Y5OJAXdaBm65nzkKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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