SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '964247890888f421a0b28ecd3703b3302829c8e28cd6bdd5033b56c2e46cbd4e' 
  AND token = 'cgY8DeTodj0bV4UuFNe+ouw0EFuyWSU7lDx3yIJaTRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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