SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cabefddf7beec55c01889fe930cb09e5a461a87e804797d04cd08ea0a05106e7' 
  AND token = 'Xa8bWu7szk2nSOMQLbNYEruK1yHlAk6Q8eNzQHVkMu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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