SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25bb90b704793354be4907ebd0b98e2db45104652857dedaa7f63cab54ec878d' 
  AND token = '658DZraOFXa8zW0aLdcoJ6bEfhSFQXhZwBMM8wsiP8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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