SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e5a0e7d9683c2e9de0a05c6b39c686f15395076f8bc003528a2764c1e6d130b' 
  AND token = 'LdP5ujXP0uFMAakCAB+UOxMbJRRQk8HD6OYNNFEAUUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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