SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6356c794e0a7e993c73a3c5525a1b6604d923b2760393e2f7b3ffbe484033bbd' 
  AND token = 'Pk1Bx9OddEGzRbL5kCS+nnqJxIhQhzbvpjgzmBeBHO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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