SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62d5e7a8c963b333af482ef57edef0f3ee23c4b7312475b84e6b96d3837cc409' 
  AND token = 'Kg4N2VqkzH/vwJn8yEVqDwgLXbzfBNGpAwR1+jWJNyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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