SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed908088d4294262ef3d7102979fb79f4223c0f45b21efaa5bfe3ba5ab0a6714' 
  AND token = 'AqEbldU7d7IOCXi9m81dZUeiGiyaK12k77PSd1Opef0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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