SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '890e12562a9adf5bcbeaed07c18cfc45c1956a9b0375ece27ac99126cc9fa8f1' 
  AND token = 'brnLyA7lvAhARUqejtaHnhmyGegOrIR0UIQsAuMyipo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}