SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e271c52bb13fbdcab18fde19ae7404d893fa3cf54799693cc8480a6d98193a9' 
  AND token = '3GWckejaqowsDkoTWU2HpKPXqCYVv/WZTduUsCj7atU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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