SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c37f14534b00a203b7e11f4c9a151799cd3538ed4cf81f0468760f413fdc4f75' 
  AND token = 'bPZcwYCatR7j8OlInv2CYnIQbwgL9j4tznS40GuRt6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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