SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3f463b5c21f13fca438a2abe9c04b7270a0e7f0a754405f201b0e1e48d739ef' 
  AND token = 'JglpnD5ljjXVUY04xUC4d74I+p+TcEaBGxISForJuXY=' 
  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"
    }
  }
}