SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c22f3877077fc7f38e38972b2e6142d76dc6b51ab19e897054ae3558d657f9c3' 
  AND token = '9XchQLrpU1huIuC3E2CA4ajIw98J0XPu8GIvSzp/H/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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