SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0abbdf4b903a20759e912b68d949cd06452823e5b5722f5300b4e76295e1766d' 
  AND token = 'JlYJauMs53gfc/QieqUBrn1ChcoqBSHlxwpK2sT9rzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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