SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca4eba1fa626724dd38c1a0abfe714b6c825759ac2d75d8531806d01f6704f7a' 
  AND token = 'ofGqR9kmBKpJu7LhYB1NB2dd3Lpj9GlTKh6ogQH80DQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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