SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '866bd842e2080667e534ee15aeea8105485502e3c11858b0b189e8353eb42b23' 
  AND token = 'f93gJqGzr1ygZZfuivVg0pV4u8TAh2TgU0983zjv21Y=' 
  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"
    }
  }
}