SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8be4bfe6ab67b21eb5f6bf729a7dc4d4caf1ee880e7ebc9fa761b15d6d85e160' 
  AND token = 'YNht0LsHNrUXiLUzO5Swhv98TIOIHUawtzpbHNOBabg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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