SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5811646157c9e86c9ed319c6e344b51e089507facd3291d26bdd3825624002a0' 
  AND token = 'PXM0fsqCLzAYUIqFR4FpVgoXBPRxKQ0n6DkcBlXjHWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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