SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f499a682d46bde8ff52ac624daa80cb0562840360ca37229eee311db7e5a85b0' 
  AND token = 'fsujSqdPN/qz7PMgMjd4v++F8ZxsodsIjfJ3IESBUKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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