SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e62e2af33505b45927e554160d6d18f0f3acd684b6b9ec4ba6c98c638216ee7f' 
  AND token = 'iOxwBwPbSTjwC3M+M7GCWMbG4zpj/TQ+fQHorXJCmaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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