SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '461a7d49616ab3a3fc1793c203e10f00c9cb7d487ab93bb35c08eed946a15e80' 
  AND token = 'Ly6ZH/q7UpvNxZTgBGpgkXgU/hvsL7qRoWFVbBW2U60=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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