SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cda0401474584c7320984075e67c4cc65021f6748f9a07d3e60664c30344019' 
  AND token = 'BJlMnkwgOOCdkDn150UdQgbTP52ZyHRILQ/5Udws3uU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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