SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c58e26e2276e5a87b9049366b993dc4ce900b383b6e0ffbef57b5bd928b9bed4' 
  AND token = 'pkb1tXaLNiopHaMSLTgDMkVY4Iw01q8638z2xLUaDEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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