SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0dc0c561c2afac5df9e7813459f6cacada0fda4d0a458f2254dc233bcf9cfcff' 
  AND token = '6e3dU9DYUJyaKBNgjWgC1AhYKdNWY5JoIL+zOQe2bMU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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