SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58d67e1caaf0697d31d285ff1b7cea255eb58114e2df5032f1ee092bf5072481' 
  AND token = '7IixHKDdSESOb3EoZ9Q7A++2igFBie7AtwxEKkBeqmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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