SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae940e6a01e38d8ef6040c0df33a3a4e2ae670be0f20cd2ce44310f40c81d12c' 
  AND token = 'OTUjaqMZKKe5OySW4dur6TA/HNZvFNVWOGdZK4NQSfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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