SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce603ff269562d0d653740604304d231e0a252724493d6011aece25628831f6e' 
  AND token = 'Tug97oMJVblt+cWoSHivnYrtZBgLGqVq0ThCgGkmNdA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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