SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce0246371e6b93e61a43ba3526b9dc5241f049e763f8c082fc5922e1dd4f14e3' 
  AND token = 'j7e/f0fXWsFXCYdcil8kH8HdFclbtVw9oRCEw/xCRh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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