SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f1c322a0061f73031f67c6933fed29eca6e56e19d9d250908f410eebaa19e04' 
  AND token = 'nQd7aCHt/w3EltIOiedWKGMKhiy2j5oKeuB9Ns4UKB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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