SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4dc33872f91e75183cd2e067cb8452678e224e315aaab90d1c3564f87412422' 
  AND token = 'GuKsqd8j0tyUFoYbc56RQ16QcJlFixSiETazfrDIAzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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