SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd769d5228f0abd80759e8dab63364703d6d3aaf505f58a664af85938a867670b' 
  AND token = 'GlV2lNPaJKCYbl1E1HTyZY6+dJvujYitWltoaHZaNnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}