SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f186bc62bc9d4c83ccd214dbb7769fa3a3b6c83b59d00ecac208cc7218a84d5c' 
  AND token = 'xidw2saTNQEO5DesjVCHkQpUlu6v5C4l458ZQPUvpsU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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