SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94073a49e6e50472686d93accd1084ea4db3d92f7278543de3ce6c764356965c' 
  AND token = 'Pcs1cWwVuPHaLUaPGU/JLlkpbrAJ3No0Rg6RisSESKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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