SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bb75844eb64e53e3e336809bc5cac3760cbc4a220f415a31f9297370ee9d408b' 
  AND token = 'V0LKVfL1umu6nUrBrsPGAIJUx+eTmuF9g3nb0+RG8i8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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