SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca237b2243b1ee54a86bb4a66a3d2b5a1954f2bef5e3cdf33dcba00642b9b7d7' 
  AND token = 'VdwfwYBn5LapB/C6HoYo8Q2ZmTDBLbqBPAyoIIGtidw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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