SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58bf86cdd0b47765183c9b2c553e039c8ce0b7e87f20f3aeb447088e3e434b25' 
  AND token = 'nGttXpxq5TrZMESEgYgXojstZc6Zj5ATOgTiqrxcEd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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