SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fddf98b68c544ffe1a764cbbf3e3099f14e5b275a8e2edacb392b31cff20162' 
  AND token = '4vDsZyAmF8nuQ9qWjr7CuT3svSIRg79OEPsVRLgbdtM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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