SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a82d566d12c0bd5060dd77b0abd8059a1952e0fb707e5b79a3425b5273bf78eb' 
  AND token = 'gnLvMBG4oUCQS+hoREPhboGez7HtDtARTbQwgdb4BIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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