SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b85fe4ad927d1a749f6555b12a9f54c61f472beaebb4884573b01b44b94fdf66' 
  AND token = 'I290zRABwoB9o+5tKklr7LzeMqyxDBQP2SSJX7Atmn0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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