SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e127a5d10839e70dc5378ef1ec22dfbb56fcb69d96c72404427035507dcd80c' 
  AND token = 'a1SMcucqi4M5JEf+OhwcNAAHLKVbAmPq4LmlSeNiK08=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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